Martin pescatore del paradiso comune

Identificazione

This kingfisher has a red bill, a dark turquoise cap with brighter blue edges, blackish cheeks, and bluish-black upper parts. The under parts are white and the under-wing coverts are blue and white. The central tail feathers are elongated and their base is blue. It is similar in appearance to the buff-breasted paradise kingfisher (Tanysiptera sylvia) apart from the colour of the breast, and in some parts of Papua New Guinea, both birds coexist.

Tassonomia

The common paradise kingfisher was first described by the English zoologist George Robert Gray in 1859 based on specimens collected by Alfred Russel Wallace near "Dorey" (modern Manokwari in western New Guinea). Gray coined the current binomial name Tanysiptera galatea. The genus Tanysiptera had been introduced by the Irish zoologist Nicholas Aylward Vigors in 1825. The name Tanysiptera is from classical Greek tanusipteros meaning 'long-feathered'. The specific epithet galatea is from Greek mythology: Galatea was a sea nymph.<p>There are 15 recognised subspecies. Of these three occur on mainland New Guinea, 11 on the Maluku Islands to the west of New Guinea, and two on other islands.<p>The Biak paradise kingfisher (Tanysiptera riedelii) and the Kofiau paradise kingfisher (Tanysiptera ellioti) have sometimes been considered as subspecies of the common paradise kingfisher.

Nome scientifico

Tanysiptera galatea

Autorità

Gray, GR, 1859

Ordine

Coraciformi

Famiglia

Alcedinidae

Genere

Tanysiptera

Areale e habitat

The common paradise kingfisher is found in the forested interior of New Guinea and on some of the offshore islands to the north. Its distribution is rather patchy and it mostly occurs below 500 m (1,600 ft) on the mainland and 820 m (2,700 ft) on Karkar Island. On some islands it is replaced by sister species; the Biak paradise kingfisher (T. riedelii) on Biak Island; the Kofiau paradise kingfisher (T. ellioti) on Kofiau Island; and the Numfor paradise kingfisher (T. carolinae) on Numfor Island. It seems that each of these island species originated from founding T. galatea birds which became isolated from the mainland birds and underwent a "genetic revolution". There were no particular biotic factors involved, but there was sufficient variation among the founding birds to encourage speciation, and the assortment of genes that the birds on each island received was later undisturbed by the inflow of alien genes.

Migrazione

Resident species

Comportamento

This species is common and mostly non-migratory, although some birds move out of monsoon rainforest in the dry season. A pair will defend a territory of 0.3 to 0.5 hectares (0.7 to 1.2 acres). The nest is made in an active termite nest in a tree. The termites build a termitarium against the tree trunk and the birds excavate a hole in its earthen wall, which can be as much as 15 cm (6 in) long leading to a 13 cm (5 in) chamber at the end. They usually try several sites before selecting one. A clutch of about five eggs are laid between November and March and both parents care for the young.<p>The diet consists of such invertebrates as earthworms, grasshoppers, beetles, caterpillars, centipedes and snails, and occasionally lizards. The bird perches upright on a low branch, remaining stationary for long periods, apart from occasionally twisting its head or flicking its tail. On seeing movement below, it swoops to the forest floor to pounce, returning with its prey to the branch. The victim may be dismembered, or subdued by bashing it against the branch. Some insects are plucked off foliage, while earthworms are sought by foraging through the leaf litter and probing the leafmould with its beak.

Conservazione

Tendenza della popolazione

declining